Method For Determination Of Uric Acid Research Articles

Colorimetric Determination of Uric Acid in Live samples

A simple, sensitive and precise colorimetric method for uric acid determination was described. The method based on the complexion reaction between uric acid, potassium ferricyanide, and ferric chloride in hydrochloric acid medium to form blue colored charge transfer complex measured at maximum wavelength 752 nm. The optimum conditions obtained were volume 0.3 ml for hydrochloric acid, 1.25 ml for both potassium ferricyanide and ferric chloride solutions, 60?C and 8 minutes as maximum temperature and time of reaction, the order of mixing additives was uric acid, ferric chloride, potassium ferricyanide, and hydrochloric acid. The highly accurate and precise results obtained with RSD%, Recovery%, Ere%, and D.L were (0.755 to 4.376), (99.676 to 97.831), (-0.033 to -2.169), and 0.1569 µg mL-1 respectively, the calibration graphs were linear in the concentration range of (2.0-200µg ml-1), the . molar absorptivity (5937.473L mol-1 cm-1) The proposed methods were successfully applied for the determination of uric acid in serum and urine samples for twenty persons.

Optical spectral sensor for the assessment of uric acid kinetics during hemodialysis treatment

The dual-wavelength direct spectrophotometric method for uric acid determination in effluent dialysate and deep UV LED based optical spectral sensor for non-invasive online hemodialysis monitoring were developed. The time profiles of uric acid concentration in effluent dialysate were recorded for a group of 12 patients and 88 hemodialysis sessions by means of the sensor. The parameters of the double-pool kinetic model for each session were assessed and analyzed. The feasibility of online optical monitoring in the UV region as a useful and convenient tool for the experimental investigation of uric acid kinetics during hemodialysis was demonstrated.

Nitrogen-doped carbon nanodots prepared from polyethylenimine for fluorometric determination of salivary uric acid.

Stable and low-cost carbon dots (C-dots) were prepared from polyethylenimine (PEI) by a hydrothermal method. It is found that the fluorescence of the C-dots (best measured at excitation/emission wavelengths of 365/473nm) is quenched by selective oxidation of surface PEI by periodate but recovers in the presence of uric acid (UA). It is assumed that this is due to the selective reduction of the nitrone groups to hydroxylamine groups by UA. The findings were used to design a fluorometric method for determination of UA that has a 2.3nM detection limit. This is lower than that of reported fluorometric and enzymatic assays. The performance of the method has been validated by determination of UA in samples of human saliva. It is found that the results agree well with those obtained by a commercial UA assay. Graphical abstract Schematic presentation of the polyethylenimine (PEI) carbon nanodots (C-dots) as a fluorescent probe for uric acid. Their fluorescence is quenched by periodate (IO4-) due to oxidative formation of nitrone groups, an subsequently restored due to reduction by uric acid (UA).

THE DEVELOPMENT OF CONDUCTOMETRIC BIOSENSOR FOR DETERMINATION OF URIC ACID CONCENTRATION IN HUMAN SERUM USING SCREEN PRINTED CARBON ELECTRODE (SPCE) – NATA DE COCO

The control of uric acid is important. A high level of uric acid can cause gout disease. Therefore a simple, fast, and accurate method for uric acid determination is required. In this research a conductometric biosensor has been developed by SPCE – Nata de coco for uric acid determination. The prepared biosensor was optimized to get a good performance of biosensor and it is applicable for human serum samples. The optimized variables were enzyme concentration, membrane thickness and pH solution. The various enzyme concentration were 6 μg/mL; 12 μg/mL; 18μg/mL; 24 μg/mL. The various membrane thickness were 5 μm; 10 μm; 15 μm. Meanwhile, the various pH solution were 7; 7.5; 8; 8.5; 9. The optimum enzime concentration was 18 µg/mL with the membrane thickness and pH were 5 µm and 8, respectively. The prepared biosensor can determine the uric acid concentration at range of 0 – 1.2 ppm with the sensitivity of 7.74 µS/ppm and the limit detection is 0 ppm. The biosensor was applied to uric acid detection in human serum with accuracy of 95 %.

THE DEVELOPMENT OF CONDUCTOMETRIC BIOSENSOR FOR DETERMINATION OF URIC ACID CONCENTRATION IN HUMAN SERUM USING SCREEN PRINTED CARBON ELECTRODE (SPCE) – NATA DE COCO

The control of uric acid is important. A high level of uric acid can cause gout disease. Therefore a simple, fast, and accurate method for uric acid determination is required. In this research a conductometric biosensor has been developed by SPCE – Nata de coco for uric acid determination. The prepared biosensor was optimized to get a good performance of biosensor and it is applicable for human serum samples. The optimized variables were enzyme concentration, membrane thickness and pH solution. The various enzyme concentration were 6 μg/mL; 12 μg/mL; 18μg/mL; 24 μg/mL. The various membrane thickness were 5 μm; 10 μm; 15 μm. Meanwhile, the various pH solution were 7; 7.5; 8; 8.5; 9. The optimum enzime concentration was 18 µg/mL with the membrane thickness and pH were 5 µm and 8, respectively. The prepared biosensor can determine the uric acid concentration at range of 0 – 1.2 ppm with the sensitivity of 7.74 µS/ppm and the limit detection is 0 ppm. The biosensor was applied to uric acid detection in human serum with accuracy of 95 %.

Dual-wavelength method and optoelectronic sensor for online monitoring of the efficiency of dialysis treatment

The absorption spectra of effluent dialysate in the ultraviolet region were investigated. A novel dual-wavelength spectrophotometric method for uric acid determination in effluent dialysate and an optoelectronic sensor based on UV LED were developed. Clinical trials of the proposed sensor were carried out in the dialysis unit of St. Petersburg Mariinsky Hospital. The relative error of measurement for the concentration of uric acid does not exceed 10%.

A Novel Method for Uric Acid Determination Using CdS Quantum Dots as Fluorescence Probes

AbstractA novel method has been developed for uric acid analysis based on the quenching of fluorescence emission from CdS quantum dots by uric acid. Also, the effect of the presence of different surfactant agents, in order to improve the fluorescent signals of the CdS QDs, has been investigated, and the cetyltrimethyl ammonium bromide (CTAB) was selected. Under optimum conditions, the calibration graph was linear over the range of 0.1 ng/mL to 12.0 ng/mL (r = 0.9950). The limit of detection (S/N = 3) was 0.1 ng/mL. The RSD for ten determinations of 5.0 ng/mL uric acid was 3.5%. The method was applied to determine uric acid in human serum and urine sample with satisfactory results.

Simultaneous Immobilization of Uricase and Peroxidase to Copolymer of Acrylonitrile with Acrylamide

ABSTRACTA method for individual and simultaneous covalent immobilization of uricase and peroxidase to copolymer of acrylonitrile with acrylamide was presented. The immobilized enzymes revealed slight change in their pH optima and an appreciable increase in their temperature optima, Km and activation energy compared to data for the soluble enzymes. A substrate inhibition of the soluble and immobilized peroxidase at high substrate concentrations was established. A little glass column packed with immobilized enzymes was used for manual uric acid determination in blood sera. The method was characterized by high analytical precision and reproducibility. The developed method is economical (the enzyme-carrier conjugate may be used more than 200 times) and easier to perform than the manual methods utilizing soluble enzymes. The established manual method for uric acid determination in biological fluids is suitable for clinical laboratory diagnostics and for work in small clinical laboratories.

A Method for Uric Acid Determination in Poultry Digestibility Trials

Evaluation of the amount of uric acid in chickens’ excreta was examined in order to determine nitrogen catabolism and to estimate fiber correctly by the Van Soest method (ADF). Uric acid was determined by an enzymatic method with a colorimetric test employed in clinical chemistry, suitably modified. Gross fiber, determined by the Van Soest method, was washed with a .5% solution of Li2 CO3 and then uric acid was determined on the basis of weight loss. The mean values of uric acid were determined according to the two methods previously described, 2.643 g/100 g and 2.633 g/100 g of fresh excreta, respectively.